test(pwsh): restore product-default deadline in loader composition

The first call pays the full pwsh cold-start latency (spawn + .NET +
PSReadLine + Defender) inside the tool deadline. A 60s bound on the fully
loaded self-hosted Windows pool is exceeded often enough to reset the
session mid-test: two master CI runs (2026-09-01, runs 33524764567 and
33534262413) each failed at ~62s with the second call observing a fresh
session (cwd back at root, env empty). 300s matches the product default
so cold start no longer races the budget.

packages/shell/tool-pwsh-persistent/tests/loader-composition.spec.ts

@@ -95,11 +95,16 @@ describe.skipIf(!hasPwsh)('persistent pwsh through a real cordis.yml Loader comp
       '    idleSilenceMs: 300',
       '    handoffGraceMs: 300',
       '    scrollbackLines: 20000',
-      '    timeoutMs: 60000',
+      // The first call pays the full pwsh cold-start latency (spawn + .NET +
+      // PSReadLine + Defender) inside the tool deadline; a 60s bound on the
+      // fully loaded self-hosted Windows pool is exceeded often enough to
+      // reset the session mid-test (2026-09-01, two runs ~62s each). 300s
+      // matches the product default so cold start no longer races the budget.
+      '    timeoutMs: 300000',
       '    disposeGraceMs: 500',
       "- name: '@deepseek-ai/dsh-tool-pwsh-persistent'",
       '  config:',
-      '    timeoutMs: 60000',
+      '    timeoutMs: 300000',
       '',
     ].join('\n'))
 
@@ -166,5 +171,5 @@ describe.skipIf(!hasPwsh)('persistent pwsh through a real cordis.yml Loader comp
     const exited = text(await execute('exit', 'exit'))
     expect(exited).toContain('next pwsh call starts from the workspace')
     expect(text(await execute('after-exit', 'Write-Output "$PWD"'))).toBe(root)
-  }, 120_000)
+  }, 300_000)
 })